Does anyone know where to find the sheet metal or tin plates with holes in them that are used for fireblocking around 1 1/2", 2" PVC pipes, and copper water lines?
I've seen them in 2 different houses and I was talking to one of the building inspectors and he was telling me that he wants to see no more than 1/8" gap around pipes going through the top plate in a finished basement. I couldn't find them at Lowe's.
Or does anyone have any other ideas for fireblocking besides the caulking?

Interesting - this is a not a requirement where we live
I could not find metal ones - if I was doing this, I think metal would be a last resort. "Great stuff Pro" seems to be approved and there are a number of caulks specifically for this purpose.

http://www.nettechdi.com/firestop_a.htm
Rector Seal - The Name You've Trusted for Years (http://www.rectorseal.com/index.php?site_id=1&product_id=205)
http://www.fomo.com/powerpoint/Understanding-Fireblock.pdf
Fireblock (http://greatstuff.dow.com/greatstuff/pro/fireblock.htm)

I also read that some jurisdictions allow fibreglass batts filling the stud wall for 16" above where the hole is.

Best bet is to ask your inspector again if he has a preference.